Polishing pad having grooved window therein and method of forming the same

Abstract

A polishing pad having grooved window therein is provided. The polishing pad comprises a polishing layer and a window, wherein the polishing layer has at least one first groove therein and the window has at least one second groove therein. More particularly, the first groove is deeper than the second groove. The polishing pad having a grooved window therein has advantages of providing precise endpoint detection and thereby reducing or resolving defect problems.

1. A method of forming a polishing pad, comprising:
 forming a window in a polishing layer; and 
 forming at least one first groove in the polishing layer and at least one second groove in the window, wherein the first groove is deeper than the second groove, wherein before the step of forming the first groove in the polishing layer and the second groove in the window further comprises: 
 chucking the polishing pad with a chuck apparatus, wherein the chuck apparatus has a recession portion corresponding to the window so that the window in the polishing layer is deformed. 
 
     
     
       2. The method of forming a polishing pad according to  claim 1 , wherein the chuck apparatus comprises a vacuum chuck apparatus or an electrostatic chuck apparatus. 
     
     
       3. A method of forming a polishing pad, comprising:
 forming a window in a polishing layer; and 
 forming at least one first groove in the polishing layer and at least one second groove in the window, wherein the first groove is deeper than the second groove, wherein before the step of forming the first groove in the polishing layer and the second groove in the window comprises: 
 chucking the polishing pad with a chuck apparatus, wherein a support layer is disposed between the chuck apparatus and the polishing pad, and the support layer has a recession portion corresponding to the window so that the window in the polishing layer is deformed. 
 
     
     
       4. The method of forming a polishing pad according to  claim 3 , wherein the chuck apparatus comprises a vacuum chuck apparatus or an electrostatic chuck apparatus. 
     
     
       5. A method of forming a polishing pad, comprising:
 forming a window in a polishing layer; and 
 forming at least one first groove in the polishing layer and at least one second groove in the window, wherein the first groove is deeper than the second groove, wherein before the step of forming the first groove in the polishing layer and the second groove in the window further comprises: 
 forming a recession portion in the backside of the window; and 
 chucking the polishing pad with a chuck apparatus, wherein the window in the polishing layer is deformed because of the backside recession portion of the window. 
 
     
     
       6. The method of forming a polishing pad according to  claim 5 , wherein the step of forming the recession portion in the backside of the window comprises performing a mechanical process or a chemical process. 
     
     
       7. The method of forming a polishing pad according to  claim 5 , wherein the polishing layer and the window are formed with a molding process, and the step of forming the recession portion in the backside of the window is by disposing a sacrificial material stacking with the window within a mold when performing the molding process. 
     
     
       8. The method of forming a polishing pad according to  claim 5 , wherein the polishing layer and the window are formed with a molding process, and the step of forming the recession portion in the backside of the window comprises providing a mold having a protrusion corresponding to the window position. 
     
     
       9. The method of forming a polishing pad according to  claim 5 , wherein the chuck apparatus comprises a vacuum chuck apparatus or an electrostatic chuck apparatus. 
     
     
       10. The method of forming a polishing pad according to  claim 5 , further comprising a step of leveling the backside of the polishing pad after forming the first groove and the second groove. 
     
     
       11. The method of forming a polishing pad according to  claim 10 , wherein the step of leveling the backside of the polishing pad comprises forming a transparent material at the recession portion. 
     
     
       12. The method of forming a polishing pad according to  claim 10 , wherein the step of leveling the backside of the polishing pad comprises removing the backside of the polishing layer.